1. Field of the Invention
The present invention relates to a pad support device for supporting a pad which is to be pressed against an object.
2. Description of Background and Relevant Materials
FIGS. 1 and 2 depict examples of pad supports known in the art.
FIG. 1 is a side view illustrating an arrangement of an example of a pad support device of a conventional electronic still camera, in which a jacket accommodating a magnetic disk is pressed by a pad.
In FIG. 1, a spindle motor (not shown) or the like is mounted on a main body 1, and a holder 2 and a cover member 3 are rotatable about the shaft 7 of the main body 1.
A support plate 4 is movably mounted on the cover member 3, and a pad 5 is attached to a lower surface of the support plate 4.
Springs 6 are urged in a direction for separating the support plate 4 from the cover member 3.
FIG. 2 is an enlarged perspective view of a pad support device in FIG. 1.
In FIG. 2, a spindle motor 11 is mounted on a base 16 of the main body 1, bosses 12 are fixed to the base 16, each boss has a hole 15. Each of the mounting screws 13 passes through the center of respective spring 6 and engages the support plate 4, the support plate 4 being movably attached to the cover member 3 by the mounting screws 13, between the support plate 4 and the heads of the mounting screws 13. Adjustment screws 14 are threaded into the support plate 4.
The springs 6 are disposed at three locations about the pad 5 to enable the support plate 4 to be pressed against the main body 1 substantially in parallel with the main body 1.
FIG. 8 shows an example of a jacket used in the electric still camera. When the cover member 3 and the holder 2 are released from the main body 1 and a jacket 31 accommodating a magnetic disk 34 is inserted into the holder 2, the shutter 32 of the jacket 31 is released and a magnetic disk 34 is exposed. When the cover member 3 is depressed downwardly in FIG. 1, the cover member 3 and the holder 2 are rotated clockwise about the shaft 7.
When the holder 2 is rotated to a predetermined position, it is held in abutment against the base 16 and stopped.
When the cover member 3 is rotated to the predetermined position, the pad 5 is held in abutment against the magnetic disk 34 which is exposed from the jacket 31. As shown in FIGS. 3 and 4, when the cover member 3 is further rotated by a slight amount, one of the adjustment screws 14 is held in abutment against the spindle motor 11 and the other two screws pass through the holes 15 of the bosses 12 and the extreme end of each screw is held in abutment against the bottom of the hole 15.
The cover member 3 is stopped in this state and locked to the main body 1. The height of the pad 5 in this case can be adjusted in such a manner that the adjustment screws 14 are rotated to advance the pad 5 or to retract the pad from the support plate 4.
At this time, the magnetic disk 34 in the jacket 31 is placed on the spindle motor 11 and rotated in the jacket 31.
When a magnetic head (not shown) is held in abutment against the magnetic disk 34 from the opposite side of the pad 5, the magnetic disk 34 is slightly elastically deformed to project into the interior of a groove 5A of the pad 5 and brought into close contact with a magnetic head 41 (FIG. 11). The magnetic head is moved in the radial direction of the magnetic disk 34 along the groove 5A of the pad 5 in this state, so that data is recorded and reproduced.
The vertical vibrations of the magnetic disk are absorbed by the elasticity of the magnetic disk itself, the pad 5 and the springs 6.
When the cover member 3 is unlocked from the main body 1 and rotated counterclockwise about the shaft 7 to a predetermined position in FIG. 1, the locking portion (not shown) connected to the cover member 3 is held in abutment against the holder 2, and thereafter the holder 2 is rotated together with the cover member 3. The pad 5 is set to be located above the holder 2, when the locking portion is held in abutment. Therefore, when the cover member is rotated to the predetermined position, the jacket can be taken out of the holder 2.
As described above, the conventional pad support device is arranged such that the three springs 6 are disposed around the pad 5 to thereby press the support plate 4 (pad 5) against the magnetic disk. This conventional arrangement has several drawbacks in that the number of parts is increased and many assembly processes are necessary. Furthermore, the urging force tends to be unbalanced by the variation, deterioration with age and the like of the respective springs 8, whereby the pad is unstably held.